Author Topic: Solar heat storage  (Read 72 times)

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Offline CG

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Solar heat storage
« on: August 22, 2022, 08:17:22 am »
I have been dreaming of a way to store solar heat, to keep my house warm for many years. Many obstacles have prevented me from doing anything about it.
About 57 years ago I made a parabolic trough solar collector, to heat water.( In Michigan.)
I only exposed it to the sun for about 15 minutes and the water got so hot that it burned my hand.
My idea was to collect the heat this way then store it in an insulated tank to be extraxtedcat a later time to keep us warm.
I'd like to do an experiment to see how long a well insulated container can store hot water. How long would the water stay hot if not disturbed?
I have some styrofoam around so I guess I'll try it.

« Last Edit: August 22, 2022, 08:21:27 am by CG »

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Offline Caleb

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Re: Solar heat storage
« Reply #1 on: September 09, 2022, 06:16:36 pm »
Sand batteries?  Sounds like geothermal though.


Offline Caleb

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Re: Solar heat storage
« Reply #2 on: September 09, 2022, 07:52:58 pm »
I went through our gas bills for a year:
Jan 182 CCF
Feb 153 CCF
Mar 109 CCF
Apr 68 CCF
May 18 CCF
Jun 15 CCF
Jul 21 CCF
Aug 91 CCF *
Sep 23 CCF
Oct 46 CCF
Nov 117 CCF
Dec 140 CCF
* Extended power outage; running on generator
During the summer, our gas usage is primarily the water heater which averages out to around 19 CCF/mo
Total heating season (Oct through April) less 19 CCF/mo for water heater = 682 CCF which I believe is equivalent to 20 MW-hr
The sand battery as presented could store 8 MW-hr with the sand at 600 deg C
Just looking at the worst three months (Dec, Jan, Feb) -> 12 MW-hr
So for seasonal heating, we'd need about 1.5 sand batteries as presented (150 tons of sand).  It would take a resistance heater to get temperatures needed to store that amount of heat, so I suppose it would have to come from solar panels.  A 10 kW array operating 6 hours per day during half the year = 11 MW-hr.